More confusing was that another shopkeeper recommended the opposite: that U.S. soldiers should always patrol with the Iraqi army. If you applied every recommendation you got talking to Iraqis on just one street, you'd wind up doing exactly what you were doing before.

When an infantryman on patrol encountered Iraqi civilians, the best thing he could do was take off his sunglasses and his helmet too, if possible, look people directly in the eye, give them a lot of deference (especially if they were older), ask them for advice, here and there interject an opinion so as to actively engage them, and plead his case without trying to lecture. That was the only way to build trust among a population that was taught for centuries how to be subjects rather than citizens.

But it is simply impossible for the soldiers to be wholly liked. There is no nice way to barge into people's houses, bristling with weapons, stomping your dusty boots on their Oriental rugs, and expect it to be a pleasant experience for them, even if you hand out candy to their kids and replace a lock you had to break with a new one. On most such occasions, only a woman and her children were present. The soldiers would find an assault weapon that had recently been fired and its magazine of 7.62mm bullets half empty: very suspicious. Did the woman know anything about it? No, she would tell the Americans, peering out below her kerchief, staring past them at the wall.

Great numbers of such seemingly ineffectual searches did work, to the extent that they kept terrorists on the run (or at least inconvenienced), forcing the insurgents to hide their guns and bomb-making paraphernalia outside their homes. But it was an inefficient way to make progress, and it bred hostility. If this keeps up, I thought, the Americans will end up being as hated in Iraq as the Israelis are in the West Bank. But it will be worse for the Americans, because they will be hated even as they are not feared.

The U.S. military was attempting to plug a dike holding back an ocean of potential unrest, and was deeply handicapped by the fact that it had no visible large-scale public-works projects to soak up crime and mass unemployment. Only such projects could show Sunni Arabs—politically weaker than ever in Iraq—the tangible benefits of democracy. Indeed, as I went out on at least one patrol a day for three weeks, riding air guard, my upper body sticking out of the top of the Stryker, the typical scenery was of bullet-marked and half-finished buildings, gray and rust-colored, a shot-to-hell cityscape in which every object—sign, streetlight, telephone pole—was bent or broken. Garbage filled every available lot. The only bustling commerce I saw, in the markets near the old city, was of the subsistence kind that does not create employment.

One local police chief told me that there were now Iraqi police and soldiers on streets where six months before there had been none, and that murders and kidnappings had been reduced substantially. Security was as good as it was going to get without a major jobs program, I thought.

"That's why I like Iraq: it's always a challenge,” said Lieutenant John Turner of Indianapolis, whom I accompanied on a patrol in Mosul. A big, fair-complexioned soldier with blond hair, Turner looked like a simple farm boy until you heard him speak with Iraqis. He talked about the promise of America, and about how he and his two sisters had grandparents who hadn't finished high school, and yet he and both his sisters had graduated from college, one from the Air Force Academy and he from Purdue.

"Sir, I am willing to die for a country that is not my own,” he told a former mukhtar, a local official, in one Mosul neighborhood, firmly but quietly. We were drinking tea with the onetime official in his home, sitting on machine-made carpets, leaning on bare cinder-block walls. "So will you resume your position as mukhtar?” Turner asked. "Brave men must stand forward. Iraq's wealth is not oil but its civilization. Trust me by the projects I bring, not by my words. Will you stand with me against the insurgents? The men who threatened you are just sixteen-year-old boys with guns but no jobs. These projects will bring jobs to your streets.”

The former mukhtar seemed to like the American lieutenant. But he said no. "I cannot resume my role as mukhtar,” he said. "They will kill me. The contractor down the street was threatened if he continued to repair the neighborhood. If you are so serious about security, then why did you Americans release prisoners from Abu Ghraib?”

Many of the detainees that had lately been released from Abu Ghraib were known to be hardened criminals from the Mosul area, and the release had undermined the credibility of American troops here. Turner replied that the decision was one taken by Iraq's own new government. The former mukhtar wasn't convinced. For Iraqis meeting with Americans in Mosul, the name "Abu Ghraib” had a different connotation than it did in the United States. Here it meant not brutality but American weakness and lack of resolve.

I thought of a conversation I'd had the previous summer in Algeria, while embedded with Green Berets who were training alongside an Algerian special-forces company. I asked one of the Algerians how his government had put down its Islamic insurgency in the 1990s. The Algerian insurgents had been arguably more brutal than those in Iraq, beheading bus passengers at roadblocks on a regular basis, making Algeria one of the most dangerous places in the world. Then the killing stopped, and the country promptly faded out of the world news, seemingly without explanation. The Algerian officer told me that suppression of the insurgents had been a simple military success story. Government forces, with the full support of a population devastated by constant terrorism—the psychological equivalent in Algeria of a 9/11 every week—had killed a lot of people (a portion of them innocent, I suspected), with no journalists in the vicinity to raise unwelcome questions. This was followed by internationally monitored elections and a steady trickle of European investors back to Algiers. The country was back on its feet. The United States, though it desired the same end result in Iraq, could not, would not, and should not apply the same means—or anything close to them. In Iraq, success would have to be accomplished through the most restricted of half-measures.